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Neuroestrogens locally synthesized in the brain are known to play a role in sexual behaviors. However, the question of whether neuroestrogens are involved in the regulation of the gonadotropin‐releasing hormone (GnRH) release is just emerging. Because previous studies in this lab indicate that neuroestradiol is also important for the pulsatile release as well as the surge release of GnRH in female rhesus monkeys, in the present study, we examined whether neuroestradiol plays a role in the estrogen‐induced LH surge in orchidectomized (ORX) male rhesus monkeys. Unlike in rodents, it is known that a high dose of estrogen treatment can result in the LH surge in ORX male rhesus monkeys. Results that the administration of the aromatase inhibitor, letrozole, failed to attenuate the estrogen‐induced LH surge, suggest that unlike in ovariectomized females, neuroestrogens do not play a role in the LH surge experimentally induced by the exogenous estrogen treatment in ORX male monkeys. [ABSTRACT FROM AUTHOR]

A proton exchange membrane (PEM) electrolyzer is fed with water and powered by electric power to electrochemically produce hydrogen at low operating temperatures and emits oxygen as a by-product. Due to the complex nature of the performance of PEM electrolyzers, the application of an artificial neural network (ANN) is capable of predicting its dynamic characteristics. A handful of studies have examined and explored ANN in the prediction of the transient characteristics of PEM electrolyzers. This research explores the estimation of the transient behavior of a PEM electrolyzer stack under various operational conditions. Input variables in this study include stack current, oxygen pressure, hydrogen pressure, and stack temperature. ANN models using three differing learning algorithms and time delay structures estimated the hydrogen mass flow rate, which had transient behavior from 0 to 1 kg/h, and forecasted better with a higher count (>5) of hidden layer neurons. A coefficient of determination of 0.84 and a mean squared error of less than 0.005 were recorded. The best-fitting model to predict the dynamic behavior of the hydrogen mass flow rate was an ANN model using the Levenberg–Marquardt algorithm with 40 neurons that had a coefficient of determination of 0.90 and a mean squared error of 0.00337. In conclusion, optimally fit models of hydrogen flow from PEM electrolyzers utilizing artificial neural networks were developed. Such models are useful in establishing an agile flow control system for the electrolyzer system to help decrease power consumption and increase efficiency in hydrogen generation. [ABSTRACT FROM AUTHOR]

A proton exchange membrane fuel cell (PEMFC) is a more environmentally friendly alternative to deliver electric power in various applications, including in the transportation industry. As PEMFC performance characteristics are inherently nonlinear and involved, the prediction of the performance in a given application for different operating conditions is important in order to optimize the efficiency of the system. Thus, modelling using artificial neural networks (ANNs) to predict its performance can significantly improve the capabilities of handling the multi-variable nonlinear performance of the PEMFC. However, further investigation is needed to develop a dynamic model using ANNs to predict the transient behavior of a PEMFC. This paper predicts the dynamic electrical and thermal performance of a PEMFC stack under various operating conditions. The input variables of the PEMFC stack for the analysis consist of the cathode inlet temperature, anode inlet pressure, anode and cathode inlet flow rates, and stack current. The performances of the ANN models using three different learning algorithms are determined based on the stack voltage and temperature, which have been shown to be consistently predicted by most of these models. Almost all models with varying hidden neurons have coefficients of determination of 0.9 or higher and mean squared errors of less than 5. Thus, the results show promise for dynamic modelling approaches using ANNs for the development of optimal operation of a PEMFC in various system applications. [ABSTRACT FROM AUTHOR]

The basilar pontine nucleus (PN) is the key relay point for the cerebrocerebellar link. However, the projection pattern of pontocerebellar mossy fiber axons, which is essential in determining the functional organization of the cerebellar cortex, has not been fully clarified. We reconstructed the entire trajectory of 25 single pontocerebellar mossy fiber axons labeled by localized injection of biotinylated dextran amine into various locations in the PN and mapped all their terminals in an unfolded scheme of the cerebellum in 10 mice. The majority of axons (20/25 axons) entered the cerebellum through the middle cerebellar peduncle contralateral to the origin, while others entered through the ipsilateral pathway. A small number of axons (1/25 axons) had collaterals terminating in the cerebellar nuclei. Axons projected mostly to a combination of lobules, often bilaterally, and terminated in multiple zebrin (aldolase C) stripes, more frequently in zebrin‐positive stripes (83.9%) than in zebrin‐negative stripes, with 66.5 mossy fiber terminals on the average. Axons originating from the rostral (plus medial and lateral), central and caudal PN mainly terminated in the paraflocculus, crus I and lobule VIb–c, in the simplex lobule, crus II and paramedian lobule, and in lobules II–VIa, VIII and copula pyramidis, respectively. The results suggest that the interlobular branching pattern of pontocerebellar axons determines the group of cerebellar lobules that are involved in a related functional localization of the cerebellum. In the hemisphere, crus I may be functionally distinct from neighboring lobules (simple lobule and crus II) in the mouse cerebellum based on the pontocerebellar axonal projection pattern. [ABSTRACT FROM AUTHOR]

Abstract: In the present investigation, we have developed a novel technique to fabricate nanocomposite materials containing SC-15 epoxy resin and K-10 montmorillonite clay. A high-intensity ultrasonic liquid processor was used to obtain a homogeneous molecular mixture of epoxy resin and nano-clay. The clays were infused into the part A of SC-15 (Diglycidylether of Bisphenol A) through sonic cavitations and then mixed with part B of SC-15 (cycloaliphatic amine hardener) using a high-speed mechanical agitator. The trapped air and reaction volatiles were removed from the mixture using high-vacuum. DMA, TGA and three-point bending tests were performed on unfilled, 1 wt.%, 2 wt.%, 3 wt.% and 4 wt.% clay-filled SC-15 epoxy to identify the loading effect on thermal and mechanical properties of the composites. The flexural results indicate that 2.0 wt.% loading of clay in epoxy resin showed the highest improvement in flexural strength as compared to the neat system. DMA studies also revealed that 2.0 wt.% doped system exhibit the highest storage modulus and T g as compared to neat and other loading percentages. However, TGA results show that thermal stability of composite is insensitive to the clay content. [Copyright &y& Elsevier]

Topographic connection between corresponding compartments of the cerebellar cortex, cerebellar nuclei, and inferior olive form parallel modules, which are essential for the cerebellar function. Compared to the striped cortical compartmentalization which are labeled by molecular markers, such as aldolase C (Aldoc) or zebrin II, the presumed corresponding organization of the cerebellar nuclei and inferior olivary nucleus has not been much clarified. We focused on the expression pattern of pcdh10 gene coding cell adhesion molecule protocadherin 10 (Pcdh10) in adult mice. In the cortex, pcdh10 was strongly expressed in (a) Aldoc‐positive vermal stripes a+//2+ in lobules VI–VII, (b) paravermal narrow stripes c+, d+, 4b+, 5a+ in crus I and neighboring lobules, and (c) paravermal stripes 4+//5+ across all lobules from lobule III to paraflocculus. In the cerebellar nuclei, pcdh10 was expressed strongly in the caudal part of the medial nucleus and the lateral part of the posterior interposed nucleus which project less to the medulla or to the red nucleus than to other metencephalic, mesencephalic, and diencephalic areas. In the inferior olive, pcdh10 was expressed strongly in the rostral and medioventrocaudal parts of the medial accessory olive which has connection with the mesencephalic areas rather than the spinal cord. Olivocerebellar and corticonuclear axonal labeling confirmed that the three cortical pcdh10‐positive areas were topographically connected to the nuclear and olivary pcdh10‐positive areas, demonstrating their coincidence with modular structures in the olivo‐cortico‐nuclear loop. We speculate that some of these modules are functionally involved in various nonsomatosensorimotor tasks via their afferent and efferent connections. Pcdh10 was expressed in particular Aldoc‐positive stripes in the cerebellar cortex (center), and in particular areas in the cerebellar nuclei (top) and inferior olive (bottom). These pcdh10‐positive areas were topographically connected (arrows) to form cerebellar modules, some of which may be involved in nonsomatosensorimotor function. [ABSTRACT FROM AUTHOR]

Comparative neuroanatomy provides insights into the evolutionary functional adaptation of specific mammalian cerebellar lobules, in which the lobulation pattern and functional localization are conserved. However, accurate identification of homologous lobules among mammalian species is challenging. In this review, we discuss the inter-species homology of crus I and II lobules which occupy a large volume in the posterior cerebellar hemisphere, particularly in humans. Both crus I/II in humans are homologous to crus I/II in non-human primates, according to Paxinos and colleagues; however, this area has been defined as crus I alone in non-human primates, according to Larsell and Brodal. Our neuroanatomical analyses in humans, macaques, marmosets, rats, and mice demonstrate that both crus I/II in humans are homologous to crus I/II or crus I alone in non-human primates, depending on previous definitions, and to crus I alone in rodents. Here, we refer to the region homologous to human crus I/II lobules as 'ansiform area (AA)' across animals. Our results show that the AA's olivocerebellar climbing fiber and Purkinje cell projections as well as aldolase C gene expression patterns are both distinct and conserved in marmosets and rodents. The relative size of the AA, as represented by the AA volume fraction in the whole cerebellum was 0.34 in human, 0.19 in macaque, and approximately 0.1 in marmoset and rodents. These results indicate that the AA reflects an evolutionarily conserved structure in the mammalian cerebellum, which is characterized by distinct connectivity from neighboring lobules and a massive expansion in skillful primates. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article Cerebellar modules in the olivo‐cortico‐nuclear loop demarcated by pcdh10 expression in the adult mouse by Gideon Anokye Sarpong et al., DOI: 10.1002/cne.24499. [ABSTRACT FROM AUTHOR]